You can do it by selecting the relevant catalog number either on the BP tab or the Items tab, and click the “Set as Default” button. The default catalog number marked as bold, and in the Items tab, a new column “Is Default” indicates the assigned status.
The default catalog number would appear by default in the then in marketing documents created for the given business partners:
Once a certain item is assigned with more that one catalog number per given BP, the first catalog number is automatically set as the default one. You can change this setting at any time.
Available in SAP Business One 10.0 FP 2102 and SAP Business One 10.0 FP 2102, version for SAP HANA. This tip and all the other tips are available on SAP Community. You can also visit the Implementation Arena for useful implementation tips.